Determination Of Pyrimethanil Research Articles

Simultaneous determination of pyrimethanil, cyprodinil, mepanipyrim and its metabolite in fresh and home-processed fruit and vegetables by a QuEChERS method coupled with UPLC-MS/MS

A QuEChERS procedure for the simultaneous determination of pyrimethanil, cyprodinil, mepanipyrim and its metabolite (M31) in fresh and processed fruit and vegetables was developed using ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS). The determination of the four target compounds was achieved in less than 6.0 min using an electrospray ionisation source in positive mode. The limits of detection (LODs) were below 0.4 μg kg−1, while the limits of quantification (LOQs) did not exceed 1.5 μg kg−1 for all studied matrices. Good linearity of the calibration curves was obtained over the range from 0.002 to 2 mg kg−1, with correlation coefficients higher than 0.999. The average recoveries of this method in apple, peach, cabbage and tomato at the five spiked levels (0.002, 0.01, 0.05, 0.20 and 2.0 mg kg−1) ranged from 81.5% to 107.3% with relative standard deviations (RSDs) in the range of 1.5–13.9% (n = 5) for all analytes. Residue levels of anilinopyrimidine fungicides in fresh and home-processed apple, peach, cabbage and tomato were also studied. The results indicate that residue levels are significantly reduced following washing, peeling and boiling, and there is no toxic metabolite of mepanipyrim (M31) which is detected during boiling. This study provides a theoretical basis for China to draw up maximum residue limits (MRLs) and protect consumers from the negative health effects of pesticide residues detected in fruit and vegetables.

Determination of pyrimethanil and kresoxim-methyl in soils by headspace solid-phase microextraction and gas chromatography-mass spectrometry.

A method using headspace solid-phase microextraction (HS-SPME) then gas chromatography-mass spectrometry with selected ion monitoring (GC-MS, SIM) has been developed for determination of trace amounts of the fungicides pyrimethanil and kresoxim-methyl in soil and humic materials. Both fungicides were extracted on to a fused-silica fibre coated with 85 microm polyacrylate (PA). Response-surface methodology was used to optimise the experimental conditions. For soil samples the linear dynamic range of application was 0.004-1.000 microg g(-1) for pyrimethanil and 0.013-1.000 microg g(-1) for kresoxim-methyl. The detection limits were 0.001 microg g(-1) and 0.004 microg g(-1) for pyrimethanil and kresoxim-methyl, respectively. HP-SPME-GC-MS analysis was highly reproducible-relative standard deviations (RSD) were between 6.7 and 12.2%. The method was validated by analysis of spiked matrix samples and used to investigate the presence of pyrimethanil and kresoxim-methyl above the detection limits in soil and humic materials.

Determination of pyrimethanil and kresoxim-methyl in green groceries by headspace solid-phase microextraction and gas chromatography–mass spectrometry

A method for determination of trace amounts of the fungicides pyrimethanil and kresoxim-methyl in green groceries, previous headspace solid-phase microextraction (HSSPME), was developed using gas chromatography–mass spectrometry and selected ion monitoring (GC–MS, SIM). Both fungicides were extracted with a fused-silica fiber coated with 85 μm polyacrylate. The effects of pH, ionic strength, extraction and desorption times as well as the extraction temperature were studied. The linear concentration range of application was 12.5–250 ng g −1 for both compounds, with detection limits of 1.8–2.0 ng g −1 for pyrimethanil and 2.8–3.1 ng g −1 for kresoxim-methyl. SPME/GC–MS analysis yielded good reproducibility (RSD between 7.4 and 15.0%). It was applied to check the eventual existence of pyrimethanil and kresoxim-methyl above the detection limits on grapes, strawberries, tomatoes and ketchup samples. The method validation was completed with spiked matrix samples. It can be applied as a monitoring tool in grapes, strawberries, tomatoes and ketchup samples.